Help! XPRT crashes when I type a specific word.

Help! XPRT crashes when I type a specific word.

Hi, this is super bizarre.
In the last few days text messaging has crashed several times, after typing the word "back". It force closes every time I type that text string. Additionally, last night I was typing in a text field in the phone browser and it also force closed when I typed in the word "back".

What the heck? Back is sort of an important word.
I'm hoping someone here can help me figure out how to fix it. Thanks in advance!